Statistics

QNT/561 Week 2 Lab – Mailing Service An accounting firm annually monitors a certain mailing service’s performance. One parameter of interest is the percentage of mail delivered on time. In a sample of 306,000 items mailed between Dec: 10 and Mar 3 – the most [...]Read more

Hypothesis Test Conducted using α= 0.025 If a hypothesis test were conducted using α= 0.025, for which of the following p-values would the null hypothesis be rejected? Solution at 0.024 Reject the null hypothesis since the p-value is less than the value of a. Explanation: When [...]Read more

QNT/561 Week 2 Lab – Random Sample of n=100 and p=0.50 A random sample of size n= 100 yielded p = 0.50 a Is the sample size large enough to use the large sample approximation to construct a confidence interval for p? Explain. b. Construct a 95% confidence interval for p. [...]Read more

Mean GPA of All Students Suppose the mean GPA of all students graduating from the University of Arizona in 1975 was 2.95. The registrar plans to look at records of students graduating last year to see if the mean GPA has decreased. Define notation and state the null and [...]Read more

QNT/561 Week 2 Lab – Town Water Department Periodically, a town water department tests the the drinking water of homeowners for contaminants such as lead. The lead levels in water specimens collected for a sample of 10 residents of the town had a mean of 2.8 mg/L and a [...]Read more

QNT/561 Week 2 Lab – Low Income Children Each child in a sample of 64 low-income children was administered a language and communication exam. The sentence complexity scores had a mean of 7.63 and a standard deviation of 8.92. True Mean Solution Tip: The mean of the sample [...]Read more

QNT/561 Week 2 Lab – Healthcare Workers Healthcare workers who use latex gloves with glove powder on a dally basis are particularly susceptible to developing a latex allergy. Each in a sample of 50 hospital employees who were diagnosed with a latex allergy based on a [...]Read more

QNT/561 Week 2 Lab – Hybrid Gas Mileage The mean gas mileage for a hybrid car is 56 miles per gallon. Suppose that the gasoline mileage is approximately normally distributed with a standard deviation of 3.2 miles per gallon. a. What is the probability that a randomly [...]Read more

Factorial (2 × 3) MANOVA – Part 3 5. Perform a factorial MANOVA on the data. Before interpreting the multivariate results of the MANOVA, check outcomes that test other assumptions for this statistic: equality of covariance matrices (see Box’s Test) and sufficient [...]Read more